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370 Uppsatser om Hollow trees - Sida 5 av 25

Kvalitet och ekonomi i utförandet av förstagallring baserat på olika gallrings- och underväxtröjningsprogram :

Stora Enso Skog has a long term contract regarding felling rights and silvicultural activities on forest owned by Bergvik Skog. In the autumn 2006, Bergvik Skog proposed a new thinning program, ?Bergvikgallring?. The new program implied an increased focus on extraction of smaller trees compared to the present thinning program, Stora Enso Skog?s ?Kvalitetsgallring?.

Om matematikundervisningens svåra konst. Ett sätt att undervisa abstrakt bevisföring

Tree fiber lengths controls properties like strength and smoothness in paper and other wood products. For forest researchers it is of interest to be able to determine the fiber lengths in standing trees. Mo?rling et al. (2003), among others, have developed methods to estimate fiber length distributions in standing trees without damaging them.

Vedrötor i stadsträd : biologi, detektionsmetoder och förebyggande åtgärder

Urban trees have very little in common with trees on natural sites, such as forests or pastures. Trees in urban environments are often planted in packed soil and in small volumes. This can lead to decreased availability of water and oxygen, as well as deteriorated ability for the soil to store nutritional elements. Also above ground the tree usually have limited space in cities. Regulations on free height over roads and cycle tracks demands high stems at an early stage of their development.

Flygburen laserskanning kopplat till skördarmätning för datainsamling till operativ planering :

The requirements for operative planning activities are increasing. The forest industry wants to gain better control over wood flow. A felling that is more market adjusted is desirable. However, this causes problems in the operative planning process because of the data collection methods used today. Data about timber assortments and data about the distribution of the tree diameter, etc., are often lacking. Airborne laser scanning is used to a greater extent than before for estimation of forest variables and should perhaps be used to the same extent in operative planning activities as well.

Analys av fiberlängdsfördelning hos gran (Picea Abies) och tall (Pinus Sylvestris)

Tree fiber lengths controls properties like strength and smoothness in paper and other wood products. For forest researchers it is of interest to be able to determine the fiber lengths in standing trees. Mo?rling et al. (2003), among others, have developed methods to estimate fiber length distributions in standing trees without damaging them.

Uttorkning av lera : Orsaker och följder

When building a house or similar the stress on the ground increases and deformations can arise. The deformations create a foundation that the building is not constructed for and damages on the building arise. The increased stress on the ground can be derived back to the building, but it is possible that the increased stress may well derive from different sources such as other buildings or trees.       The building is an older property, built in the late 19th century alternatively early 20th century, and is today used for rental housing and has suffered severe damages due to subsidence. The goal of the thesis is to find possible causes for these subsidences. The thesis was executed as a combination between literature- and casestudie. After careful studies it has been found that a probable cause for these subsidences is trees. Through field- and lab studies it has been found that the trees has effected the ground through there accumulation of water.

Naturhänsyn vid föryngringsavverkningar : En jämförelse mellan certifierade och o-certifierade hyggen

A growing number of Swedish forest owners are choosing to certify their forestry. However, there appears to be a lack of field surveys which describe differences between certified and non-certified forests concerning the degree of completed environmental considerations. In order to know to what extent certified forests contribute towards improved environmental consideration, we need studies on how large the difference is in relation to non-certified forests.Differences between certified and non-certified forest clearings were quantified through an inventory of the number of retention trees, dead trees and snags. The result showed that the retained number of the investigated parameters varied greatly between individual clearings, regardless of certification status. However, the results suggested that the certified clearings had an average higher incidence ofthe investigated parameters.

Vindfällning i naturliga och skapade bryn och kanter :

The aim of this work was to study if the edge of the forest is more resistant to heavy winds than the trees located further in from the edge, and how this edge effect changes between different types of tree species and site types. The data was collected from an electric power line going from the north to the south of Sweden. The mean value of the clearcutted area around the power line was 120 meters. The main direction of the storm in January 2005 was west-southwest and thus the power line was a perfect place for gathering a large data set. The main parameter studied was the damage frequency at the edge of the forest compared to the trees located further in from the edge (up to 100 m from the power line). Tree species mixture, soil moisture class, soil type, topography, stand height, stand height of the stand on the other side of the power line and wind exposition was estimated. The results showed a distinct edge effect. The edge of the forest had clearly lower damage frequency for all tree species. A marked difference was observed between tree species and damage frequency.

AHA in northern Sweden ? a case study : conservation values of deciduous trees based on saproxylic insects

AHA is a Swedish abbreviation of "reveal threatened park and avenue trees" and is a method to assess the conservation value of individual trees, mainly in the park environments but also in natural stands. This method has previously only been practiced in southern Sweden (Sörensson 2008). To see if this method could provide satisfactory results in northern Sweden, I have studied it in areas around the Umeå River. This was done by studying the relationship between trees with different classifications of conservation value (as classed by the AHA method) and their content of species (species richness and abundance). Insects were collected using trunk window traps in a period of 13 weeks during the summer of 2014.

Det goda hemmet och det ideala barnet : Svenska fosterhem för finska barn i Sverige genom Hjälpkommittén för Finlands barn i Uppsala län 1941-1949

Syftet med denna uppsats är att analysera mansbilden av karaktären Edward i filmen Edward Scissorhands (Tim Burton, 1990). Genom attstudera hans personlighet och egenskaper ur olika perspektiv, som kan uppfattas som både manligt och kvinnligt, har jag försökt att ta reda på vem denna utstickande karaktär är.Med hjälp av genusteorier och jämförelser av tidigare filmatiseringar som Ed Wood (Tim Burton, 1994), Sleepy Hollow (Tim Burton, 1999) och The cabinet of Dr. Caligari (Robert Weine, 1920) har jag även kunnat fördjupa mig i mansbilden av Edward. Jag har dessutom fokuserat kring Tim Burtons säregna filmskapande, men också kring stjärnskapet hos Johnny Depp, skådespelaren som Burton ofta samarbetar med.Edward Scissorhands har visat sig vara en man med både manliga och kvinnliga attribut, vilket gör honom till en icke stereotypisk man som saknar hjältemod och en muskulös kropp. Trots det så tyder inget på att han är mindre man bara för att han har mer eller mindre egenskaper som generellt uppfattas som manliga.

Tillväxt och potentiell sågtimmerkvalitet i gallringsmogna jämförelseplanteringar med Pinus contorta och P. sylvestris :

The Swedish Cellulosa Companiy, SCA, has today 280 000 ha planted with lodgepole pine (Pinus contorta var. latifolia) (?C?) which is equivalent to 14 % of its total forest area. Exotic lodgepole pine has in previous experimental stands shown a superior growth than the native Scots pine (Pinus sylvestris L.) (?S?).But also the comparison could be questioned because stand histories were was unknown and also differences in age between C and S existed.

Metoder för att undersöka effekterna av naturvårdshänsynen i skogsbruket efter den nya skogsvårdslagen

In 1994 a new Forestry Act was accepted in Sweden. One of its aims was to raise the consideration for preservation of biodiversity. Since this happened over 15 years ago there is now an interest in analyzing if the law has been effective in its purpose. In this study methods suitable for analysis are being investigated. The study contents a pilot study of methods for five parameters that can validate if the law has been followed.

Produktivitet och lönsamhet vid skogsbränsleuttag i klena gallringar : en tidsstudie av Vimek 608 BioCombi i contortabestånd

The annual demands for forest fuels increases in Sweden. At present, large unutilized biomass resources is found in young, dense forests from which about five million oven-dry tonnes (ODt) (23 TWh) could annually be extracted as forest fuel. But harvesting small trees give high logging costs and new cost-efficient harvesting techniques are therefore required. The aim was to study the productivity of Vimek 608 BioCombi in forest fuel thinning of Lodgepole pine and to calculate the economy of the harvesting and estimate the thinning quality. The time study was performed in Åmarken in the county of Västerbotten.

Träd i stadens centrala rum :

The sum of this study is to examine where trees can fit into the city today..

Produktutbud av lignoser för norra Norrland :

Ett begränsat utbud av växter kan antas påverka privatpersoners trädgårdsintresse negativt. För norra Norrland begränsas utbudet av lignoser till dem som har tillräcklig härdighet. Det kan dock antas att fler lignoser utöver de som säljs idag, har potential att användas i denna del av landet. Detta examensarbete har som syfte att ta reda på hur försäljningen av lignoser i norra Norrland ser ut idag. Vidare undersöks också om en utveckling av lignosutbudet pågår och hur arbetet med denna utveckling i så fall ser ut. Vem eller vad som kan påverka så att fler härdiga lignoser kommer ut på marknaden har varit en central frågeställning.

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